Fluid motor with emergency supply reservoir



Jan. 4, 1949. c. K. STEINS ETAL FLUID MOTOR WiTH EMERGENCY SUPPLY RESERVOIR 2 She'ets-S heet 1 Filed Jan. 26, 1944 INVEJVTORS' ATTORNEYS.

.Jan. 4, 1949. c, 5 5 ET AL 2,457,937

FLUID MOTOR WITH EMERGENCY SUPPLY RESERVOIR Filed Jan. 26, 1944 2 Sheets-Sheet 2 "11111111111110. IIIII.WIIIIIIII.E

' INVENTORS': 'az leiolzlfifiezbm HarryLHaKe,

ATTORNEYS.

Patented Jan. 4, 1949 FLUID MOTOR WITH EMERGENCY SUPPLY RESERVOIR Carleton K. Steins, Merton, and Harry A. Hoke, Altoona, Pa., assignors to The Pennsylvania Railroad Company, Philadelphia, Pa... a corporation of Pennsylvania Application January 26,1944, Serial No. 519,724

3 Claims. (Cl. 60 -57) This invention relates to power reverse gears for steam locomotives and the like, and has reference more particularly to power reverse gears of the pressure-fluid actuated type in which the shifting of the eccentric straps of the locomotive engine is accomplished by means of a doubleacting cylinder under governance of a manually operable control unit.

Power reverse gears of the kind specifically referred to are rendered useless in the event of failure of the pressure-fluid supply, or of rupture of the piping leading from the source of such supply to the control unit.

Our invention has for its chief aimto obviate of exemplifying our invention is generally of well known construction, having a double-acting cylinder I with a piston ll therein, .and a guide l2 bolted to its forward end for a cross head l3 at the outer end of the piston rod I5. Through a link l5, motion is imparted from the cross head I! to the usual eccentric rod lifting bell crank lever i! of the locomotive. Pressure-fluid is ad- 'mitted or exhausted from opposite ends of the cylinder I0 by way of ports l8 and i9 and connecting ducts and 2| in the top of the cylinder wall under governance of a control unit generally designated 22,whereof the housing 23 is directly mounted on said cylinder. The actuating means the above drawback, that is to say, to make'pos- 15-for the control unit 22 includes an engineers hand sible at least two emergency operations of the lever 25 which is fulcrumed to a stop quadrant 25, gear in contingencies of the sort mentioned. This and a link 21 which extends from said lever to a objective is attained in practice as hereinafter floating arm 28 pivotally connected to the upper more fully disclosed, through provision of an auxend of a short arm 29 fast on the rear protruding iliary reservoir in which a quantity of the pres- 20 fend of the shaft or stem 30 of the control unit sure medium is stored, and through modifications "22, said floating arm being. coupled by means of in the construction of the control unit of the rea link II with the usual cross head arm indicated verse gear which will enable utilization of the reat 32. Pressure-fluid is conducted to the control serve supply of the pressure medium for several unit 22 from a suitable supply source (not shown) emergency operations. 26' through a pipe 33. Also as ordinarily, the control Other objects, and attendant advantages will unit 22 is provided with a sector-shaped valve appear from the following description of the atelement which fits over the key end 36 (Fig. 3) tached drawings, wherein Fig. 1 is a fragmentary of the stem ill, said valve element bearing against view in side elevation of a power reverse gear for a machined seat 31 at the front of the housing 23 steam locomotives embodying our invention, por- 30 and being enclosed by a hollow cupped cover tions of the organization being broken away and piece or. cap 38 which is secured to said housing shown in section to more clearly illustrate imby a plurality of bolts 40, see Fig. 5, with interportant structural features which would otherposition of a sealing gasket at 4|. The valve elewise be obscured. ment is firmly held to its seat by a follower l2 Fig. 2 shows the front elevation of the control 35 having an axial stud 43 which is engaged in a unit for the pressure-fluid cylinder of the reverssocket 45 in the cover piece 38 and which is subing gear with certain parts removed and with a ject to the action of a helical compression spring portion of the housing of said control unit broken 48. In the face of the valve seat 31 are three away and sectioned. radially arranged ports 50, 5|, 52 (see Fig. 2),

Fig. 3 is a central cross sectional view taken as whereof the central one communicates with an indicated by the angled arrows 1II-III in Figs. 1 and 2.

Fig. 4 is a fragmentary longitudinal section taken as indicated by the angled arrows IV-IV in Fig. 3.

Fig. 5 is a view looking from the left of Fig. 2 and showing the control unit in end elevation.

Fig. 6 is a detail sectional view taken as indicated by the angled arrows VI-VI in Fig. 3 and showing the valve element of the control unit in its normal position: and

Fig. '7 is a view like Fig. 6 showing the valve element of the control unit in one of its shifted positions.

The power reverse gear chosen for convenience exhaust duct having horizontal and upward branches 53, 54 in the housing 23, the last mentioned branch leading directly to the exterior. The other two ports 5|, 52 respectively, communicate with passages 55, 55 in the valve body leading to the ducts 20, 2| which terminate at l8 and til at the opposite ends of the cylinder ill. The valve element 35 has an arcuate recess: 350 (see Figs. 3, 6, and 7) whereof the circumferential extent is such as to be capable of spanning two oi the ports 50, 5|, 52 at a time. Normally the valve element 35 occupies the neutral position in which it is illustrated in Figs. 3 and 6 with all parts of the reverse gear quiescent in the relation show: 'in Fig. 1. Upon shifting of the valve element 35 to the position of Fig. 7, pressure-fluid will be permitted to flow from the hollow of the cap 33 through the port of the communicating ducts 55, 20 and port l8 to the left-hand end of the cylinder l0, while the opposite end of said cylinder exhausts by way of the port l3, ducts 2|, 66, port 52. the hollow 35a of the valve member 36, port 50 and ducts 53, 53. Movement of the valve element 35 in the opposite direction from that shown in Fig. '7 will result in admission of pressure-fluid to the right-hand end of the cylinder ill by way of the port 52. ducts 68, 2| and the cylinder port I9, and in the concurrent exhausting of the left-hand end of said cylinder by way of the port It, ducts 20, 55, port 5|, the recess 36d of said valve element, port 60, and ducts 63, 64. The performance of the gear after shifting of the valve element 35 in either direction as Just explained, will be after a manner well understood in the art and need not therefore be described herein.

In order to adapt the control unit 22 to the purposes of our invention, we have provided its housing 23 with two longitudinally-extending parallel passages 60 and 6!, which, at the center of said housing, are connected by a vertical bore or transverse passage 62 wherein is disposed a small check valve 63. The closure disc 64 of the check valve 63 is arranged to cooperate with a seat 65 in interrupting communication between the two passages 60 and 6| under certain conditions later on explained. Normally, the check valve 631s closed as shown, but will automatically open to allow flow of pressure-fluid to the cylinder I0 during ordinary operations of the gear. From Fig. 4 it will be noted that the supply pipe 33 for the pressure-fluid is connected into one end of the pass-age 60 whereof the other end is closed by a screw plug 66, and from Figs. 2, 3 and 4 that a deviating passage with vertical and horizontal branches 6'! and 68, 69 leads from the duct iii to the hollow or cavity of the cap 38 which encloses the valve element 35 and which is accordingly in constant communication with the supply source of the pressure-fluid. For the purposes of storing a reserve supply of pressure-fluid to enable emergency operations of the reverse gear in the event that the supply pipe 33 is broken or the regular source of supply fails, we have, in accordance with our nvent DrOVlded a reservoir 10, see Fig. 1. This reservoir 10 may beformed as shown by welding a bell to the rear head H of the cylinder ID in axial alignment with the latter. A pipe 12 leading from the top of the reservoir 10 connects into one end of the passage iii, the other end whereof is closed by a screw plug 13. Thus the reservoir 10 is normally in communication, through the pipe 12 and the passages BI, 62 and in the housing 23 of the unit 22, with the fluid-pressure supply pipe 33. However, in the .event of either of the contingencies mentioned above, it will be apparent that the check valve 63 will remain permanently closed through drop of pressure in the duct 60 and thus trap the pressure-fluid in the reservoir 10, the quantity trapped being thus made available for use in emergencies. The capacity of the reservoir 10 is in practice such as .toinsure a supply of pressure fluid for at least two emergency operations of the gear. The cock shown at 15 serves as a means whereby the reservoir 10 may be relieved from time to time of condensation accumulation. It will be observed from Fig. 4 that the arrangement of the passages 60 and 6| pe 33, and the pipe I2 connected into that end of the duct 6| now occupied by the screw plug 13.

said plugs being of course correspondingly reversed in position to suit.

Having thus described our invention, We claim:

' 1. In a power reverse gear for steam locomotives and the like, a double-acting cylinder; controi means for selectively controlling flow of pressure-fluid from a supply source to the opposite ends or the cylinder; a reservoir normally in communication with the pressure fluid supply source; and means incorporated in said control means automatically operative in the event of failure of the supply source, to trap pressure-fluid in the reservoir for availability in a number of subsequent emergency operations of the gear.

2. A power reverse gear according to claim 1, wherein the control means comprises a, housin having an internal hollow, a number of passages which communicate with each other and with the hollow as well as with the supply source of the pressure-fluid and with the reservoir, and ducts leading from ports in a, valve seat within the hollow to opposite ends of the actuating cylinder; wherein the control means also comprises a valve member which normally closes both of the aforesaid ports but which is movable onthe seat to uncover one or the other of the ports to permit flow of pressure-fluid from said hollow to the corresponding end of the cylinder; and wherein the trapping means is in the form of a check valve which is interposed in one of the aforesaid passages.

3. In a power reverse gear for steam locomotives and the like, a double-acting cylinder; a reservoir for an emergency supply of pressure-fluid; and control means with a casing having therein a cavity, a pair of parallel ducts one in communication with the main source of pressure-fluid supply and the other in communication with the reservoir and a crosswise passage connecting the two ducts and the cavity, a movable control member within the cavity whereby communication may be established selectively between the crosswise passage and the opposite ends of the cylinder, and a check valve interposed in the passage between the two ducts, said valve normally permitting flow of pressure-fluid from the main source of supply to the reservoir but closing automatically in the event of failure of the main supply.

. CARLETON K. STEINS.

HARRY A. HOKE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

